Duchess Kate makes first public appearance since announcing news of baby No. 3

The royal made her first public appearance on Tuesday evening since announcing in early September that she's expecting baby No. 3. The Duchess, alongside husband Prince William and brother-in-law Prince Harry, were hosts of a Kensington Palace reception celebrating mental health workers.

The 35-year-old royal showed off her baby bump in a powder blue lace frock from London brand Temperley that hit just below her knees that she matched with a pair of black pumps and diamond drop earrings worth $3,852 from her go-to designer Kiki McDonough.

She wore her brunette tresses in a blown out style while keeping her makeup to a minimum.

Kate has stayed out of the spotlight since announcing her pregnancy -- even missing George's first day of school -- as she has been suffering from has been suffering from hyperemesis gravidarum (severe morning sickness).

The condition affects about one in every 200 pregnancies and results in severe nausea, dehydration, and low blood pressure, among other things.

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While the public knows barely anything about Kate's pregnancy thus far, Prince William has been sharing details here and there. He recently revealed that Kate has been trying to eat ginger biscuits to alleviate her morning sickness. The Duke also hinted that their bundle of joy maybe coming sooner rather than later while talking to a midwife.

On Tuesday night, Duchess Kate looked healthy as ever as she mixed and mingled with the crowd.

Kate, William and Harry have raised awareness of mental health issues with their charity Heads Together. Through several interviews and ad campaigns, the royal trio has encouraged people to speak out about their issues or be a kind ear for others.

Earlier this year, Kate candid about her own struggles with coming to terms with motherhood during a discussion with two other mothers.